1. Field of the Invention
The present invention relates to a semiconductor device, and more particularly to a semiconductor package and a method of fabricating the same. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for providing a more degree of freedom in designing a semiconductor package and improving a reliability of the package.
2. Discussion of the Related Art
Generally, a column lead type semiconductor package having leads buried in an insulator is widely used in the semiconductor industry because it is endurable to physical impacts and the leads are not bent by the exterior force. A background art column lead type semiconductor package will be described with reference to FIG. 1.
The background art column lead semiconductor package is illustrated as shown in FIG. 1. FIG. 2 is a cross-sectional view illustrating a structure of the background art semiconductor package along with the line II-II' of FIG. 1. In the background art column lead semiconductor package, an insulator 10 is formed using a molding compound, and lead bars 11 are formed to be exposed at upper and lower surface of the insulator 10. A semiconductor chip 12 is attached to the upper surface of the insulator 10 by a polyamide adhesive, and a plurality of bonding pads (not shown) are formed on the upper surface. The bonding pads are connected to predetermined parts of the lead bars 11 with corresponding wires 13, and the wires 13 and the semiconductor chip 12 are protected by a molding compound coating 14.
A fabrication method of the background art column lead type semiconductor chip package will be described in detail with reference to FIGS. 3A to 3D.
In FIG. 3A, a semiconductor package substrate is fabricated with a plurality of lead bars 11 buried in an insulator 10. The lead bars 11 are exposed at upper and lower surface of the insulator 10. To form such a semiconductor package substrate, thin metal conductive plates which will be the lead bars supported by predetermined supporting members are put in a frame. A liquid molding compound is then filled and hardened in the frame. The frame is removed and a formed structure is sliced, thereby completing the semiconductor package.
Referring to FIG. 3B, a center portion of the semiconductor package substrate of FIG. 1 is grinded to form a recess 12a.
Next, in FIG. 3C, a semiconductor chip 12 is attached onto the recess 12a and pads (not shown) formed on a marginal portion of the semiconductor chip 12 are connected with a predetermined portion of each of the lead bars 11 by wires 13.
In FIG. 3D, the wires 13, the recess 12a, and the semiconductor chip 12 are protected by a molding compound coating 14.
As described above, the semiconductor chip having the pads connected to the lead bars by the corresponding wires formed on the center portion is called a center pad type semiconductor chip. Since the center pad type semiconductor chip has the chips on the center portion, it provides a more degree of freedom in designing comparing to the other types of semiconductor chips.
However, it is difficult to apply the background art column lead type semiconductor package to a packaging of the center pad type semiconductor chip. Specifically, when pads are formed on a center portion of the upper surface of the semiconductor chip, each pad is considerably apart from the corresponding lead bar. As a result, a wiring process is much difficult to be accomplished.